Newport Sharon, Amin Nikhil, Dozor Allen J
Division of Pediatric Pulmonology, Maria Fareri Children's Hospital at Westchester Medical Center and New York Medical College, Valhalla, New York, USA.
Pediatr Pulmonol. 2009 Sep;44(9):866-72. doi: 10.1002/ppul.21078.
Exhaled breath condensate (EBC) pH reflects the acid-base homeostasis of the airway lining fluid and is up to 3 log order lower in various inflammatory lung diseases including asthma, COPD, bronchiectasis, and cystic fibrosis (CF) than in normal controls. The aim of this study was to confirm this finding in CF and determine if there was a significant change in EBC pH after treatment of an acute pulmonary exacerbation. Ten subjects with CF and a pulmonary exacerbation, and 10 healthy age-matched control subjects were studied. EBC was collected at the onset of an acute pulmonary exacerbation and after treatment with intravenous antibiotics (median duration: 14 days (interquartile range, IQR): 12-14) when the exacerbation was considered resolved. The median age for CF patients was 15.9 years (IQR: 13-18.8), compared to 18 years (IQR: 15-24.8) for the control group, P = 0.242. All CF subjects had severe lung disease, median FEV(1) = 41.5% of predicted (IQR: 30.8-46.5%). Median EBC pH in CF subjects at the onset of a pulmonary exacerbation was 6.61 (IQR: 6.17-7.91) compared to median EBC pH of 8.14 (IQR: 7.45-9.08) in the control group, P < 0.02. Median EBC pH after resolution of an exacerbation was 7.02 (IQR: 5.8-8.64), not significantly different (P = 0.667) than during the acute exacerbation. EBC pH decreased in five subjects, increased in three subjects and there was no change in two subjects. There was no correlation between EBC pH and FEV(1) either before or after intravenous antibiotics. EBC ammonia, an important buffer of ASL, was also measured and similarly found to be lower than in normal controls. EBC pH is lower in CF than age-matched controls, and did not change consistently in response to treatment of an acute pulmonary exacerbation.
呼出气冷凝液（EBC）的pH值反映了气道内衬液的酸碱平衡，在包括哮喘、慢性阻塞性肺疾病（COPD）、支气管扩张和囊性纤维化（CF）在内的各种炎症性肺病中，其值比正常对照组低达3个对数级。本研究的目的是在CF患者中证实这一发现，并确定急性肺部加重期治疗后EBC的pH值是否有显著变化。对10例患有CF且伴有肺部加重期的患者以及10例年龄匹配的健康对照者进行了研究。在急性肺部加重期开始时以及在用静脉抗生素治疗后（中位持续时间：14天（四分位间距，IQR）：12 - 14天），当认为加重期已缓解时，收集EBC。CF患者的中位年龄为15.9岁（IQR：13 - 18.8岁），对照组为18岁（IQR：15 - 24.8岁），P = 0.242。所有CF受试者均患有严重的肺部疾病，FEV₁中位数为预测值的41.5%（IQR：30.8 - 46.5%）。肺部加重期开始时CF受试者的EBC pH中位数为6.61（IQR：6.17 - 7.91），而对照组的EBC pH中位数为8.14（IQR：7.45 - 9.08），P < 0.02。加重期缓解后的EBC pH中位数为7.02（IQR：5.8 - 8.64），与急性加重期相比无显著差异（P = 0.667）。5例受试者的EBC pH值下降，3例受试者的EBC pH值上升，2例受试者无变化。静脉使用抗生素前后，EBC pH与FEV₁之间均无相关性。还测量了EBC中的氨（气道表面液体的一种重要缓冲剂），同样发现其低于正常对照组。CF患者的EBC pH低于年龄匹配的对照组，并且在急性肺部加重期治疗后其值并未持续变化。
